iMac Memory Expansion: Do It Yourself?

Apple's new iMac does not come with any instructions on how to add
memory to the computer. Of course, it really doesn't come with much
in the way of instructions for anything else, either. But Washington
Apple Pi Labs, firm believers in the motto: "The More RAM the
Better," decided that the 32 megabytes supplied with a standard iMac
was Not Enough. Particularly since memory is cheap.

So we carefully examined the iMac case and quickly concluded: we
had no idea how to get into it. After briefly considering The Dealer
Option ("Hi! Could you install more memory in our iMac? Well,
actually, it is someone else's iMac, but they gave it to us because
we are Mac gurus, but..."), we decided to be brave and fake it.

Step Zero: ground yourself. Static electricity is
invisible, but each year it kills more computers than almost any
other source except creamed coffee. Wear cotton clothing and either
cotton socks or bare feet. Wear a grounding strap, properly grounded.
(Wearing a grounding strap and failing to ground it is pointless, but
commonly done. Don't do this.)

Step One: place the iMac face down on a large beach towel.
Be sure and wash it first; getting sand in the iMac probably isn't a
good idea. We used a big blue beach towel with pictures of tropical
fish, but any clean beach towel should do. Or a soft cotton bathrobe,
or cotton bedspread, or...

Place the iMac face down (monitor down) on a clean, soft
cotton cloth. We used a large beach towel. Note the oval
handle at the end of the bottom cover. (Why cotton? It is
soft, doesn't scratch, and doesn't retain a static
charge.)

Step Two: there is a single retaining screw holding the
bottom cover in place. Remove the screw with a Phillips
screwdriver

Step Three: using the plastic handle built in to the bottom
cover, carefully pull up and out to remove the bottom cover. Figuring
out how to pull the cover off and unclip the various flanges holding
it in place will take much longer than removing the screw. At this
point you may be thinking, "This is way more complicated than
installing memory in a Power Mac G3 desktop." Then you'll realize: an
iMac is a Power Mac G3 desktop. Oh, joy.

Once the bottom cover is removed, the logic board is
exposed. Note the CD-ROM drive at the bottom, with various
cables plugged into it.

Step Four: disconnect the cables connected to the logic
board. Some of these pull out, some have twist connectors, and one is
held in place by a clamp. Take mental note of how each one connects
(or take notes on paper if you wish.) Remember that variety is the
spice of life.

Step Five: note that there is another, smaller handle at
the back of the logic board (now the "top" end of the board). Inside
the handle are two retaining screws. Remove these screws, using a
smaller Phillips screwdriver than you used earlier. Don't drop the
screws into any of the slots. (Good luck.)

Step Six: pull up on the logic board handle to remove the
logic board. Take care not to get tangled with the cables you
disconnected earlier. Place the logic board on a flat, stable,
static-free surface. Say to yourself, "I can't give up now; I've got
to put it back together again."

Once the logic board is removed, you can see an internal
fan (which just happens to be located over where the
processor normally sits). You also can't help but notice
that the vast majority of an iMac's bulk is occupied by the
monitor.

Step Seven: the memory expansion slots are under an EMI
(Electro-Magnetic Interference) shield on the center of the logic
board. This lifts off easily; it is held on by the flanges on the
sides.

Step Eight: the main memory slot is located at the center
of the logic board next to the processor. There is another one
allegedly located under the processor, but we had no desire to
check. Insert the memory module at a 45-degree angle and carefully
press down until it clips under the flanges at the sides of the slot.
The memory module should be firmly seated; don't resort to extreme
force, but don't expect the module (or the iMac) to work unless it is
firmly seated in the memory slot.

The square structure on the left of the logic board
covers the iMac's processor and memory. On the right, the
large square box is the housing for the CD-ROM drive.

Steps Nine-Fourteen: replace the EMI shield, and slide the
logic board back in place. When sliding the logic board back in
place, make sure the CD-ROM drive door fits through the slot in the
front of the iMac (you might need to slip your hand under the front
to check the alignment). Reconnect the cables, screw in the logic
board handle retaining screws, replace the back cover, and replace
the retaining screw.

Step Fifteen: plug everything back in and test the
iMac.

Step Sixteen-Thirty-seven: redo everything after you
finally admit you didn't properly seat the memory module in the
memory expansion slot. Then redo parts of the procedure again after
dropping one of the screws into a slot.